A bevy of conservative groups are lambasting former Vice President Joe Biden for being unwilling to discuss his position on packing the Supreme Court should he win this November and Democrats take control of the Senate.

The former vice president, who has urged Republicans not to confirm Judge Amy Coney Barrett to the Supreme Court seat vacated by the late Ruth Bader Ginsburg, was asked during the first general election debate if he supported calls by members of his party to pack the court or scrap the filibuster.

“Whatever position I take on that that will become the issue. The issue is the American people should speak. You should go out and vote. You’re in voting now. Vote and let your senators know how strongly you feel,” the Democrat nominee said.

Biden’s refusal to be transparent drew rebuke from conservative activists and center-right organizations on Wednesday. Jenny Beth Martin, the founder of Tea Party Patriots, echoed much of the sentiment emanating from the right.

“In last night’s debate, Joe Biden refused to say he would oppose packing with the Supreme Court with more liberal justices,” Martin wrote on social media. “That’s an idea so bad that when FDR tried it in 1937, he couldn’t get it done — even though Dems outnumbered GOPers in the Senate by 76-16.”

Others on the right were just as pointed in their comments.

In recent weeks, Democrats have begun mobilizing to keep President Donald Trump from filling Ginsburg’s seat on the Supreme Court. The move, in part, is strategic, as many fear that a Trump appointee will cement a 6-to-3 conservative majority on the nation’s highest court for the foreseeable future.

To prevent such an outcome, Democrats are attempting to obstruct the congressional confirmation process until January, in hopes that Biden will win the upcoming election and be able to propose his own candidate. As part of the effort, Senate Democrats are threatening to pack the court if Republicans move forward with Barrett’s nomination.

“If Sen. McConnell and [the] Senate GOP were to force through a nominee during the lame-duck session—before a new Senate and president can take office—then the incoming Senate should immediately move to expand the Supreme Court,” House Judiciary Chairman Jerry Nadler (D-NY) said earlier this month.